Socket for electrical devices



1951 c. METCALFE ET AL 2,536,652

SOCKET FOR ELECTRICAL DEVICES Filed July 51, 1947 l NVENTORS ATTORNEY Patented Jan. 2, 1951 Glifiord Metcalfe Ruislip; and Ralph.- Sextom, Hayes End, England, assignorsto-Electric Musical. Industries. Limited,.. Hayes, England, a... company of Great Britain Application July- 3-1", 1947;.Seriat No. 165.;204 rn- Great-Britain May 22.14346;

Section'l; Public Law 690,;Aug1 1stv 8, 1'94'6 Patent expires May-'2; 1966.

This inventionrelates-to sockets for electron discharge-tubes and the like. having contacts projecting therefrom; and the invention relates especiallybut not exclusively to sockets ior discharge tubes of the kind in: which the contacts comprise rigid pins sealed to-the vitreous. base of the tube, as distinct from the more widely known contact pins: which comprise resilient sleevesto-whioh thedeadsof 'the electrodes of the tubesare eonnectedi The objectiof the present invention is to provide-an: improved. socket such as-used 'in radio-receiversfor receiving the valvesthereof the: socket leeing simple to manufacture and to: assemble.-

According to the present invention there is: providewa-socket for electron discharge tubes and the like" having contacts. projecting; therefrom, comprising an insulating base having a plurality of apertures for receiving said contacts and having a contact-element in each of. said apertures-to which alead" can 'beconnected, wherein each of the contact elements is'provided' with a resilient portion which is'accommodatedi in said aperture and arranged to face the wall" of said aperture so that when a contact of suitable size is inserted: insaid aperture sai'd'contact is engaged by said resilient: portion and tends to be resiliently urged towards the walllof" said aperture. The invention makes possible aas'imple construction for the contact elements since the resilient portion of each contact element may comprise a length of resilient material. which is folded upon itself;

In order-that the said invention may-be. clearly understood: and readily carried into effect, the same will now be more fully described with reference to the accompanying drawings, inwhich:

Figure 11 is a top plan. view on an enlarged scale of a valve socket: in accordance with the present invention, andshowing also an attachment. member forsecuringthe socket. in position,

Figure 2 is a sectional elevation. on the line IL-IIof: Figure .1,

Figure 3 is. a plan view of a metal blank-such. as employed'to. makerthev contact elements forrthe: socket, and".

Figure..4 is a plan view; of? a. metal blank such as-empl'oyed to make the central sleeve for" the socket;

Referring to the drawing; thesocketzcomprises an? insulating base i pressed from a. suitable plastic, said basev having a plurality of circularlyarrangedapertures. 2" in each of which: is disposed acontact. element 3., only oneof the contact:elemerits: being shown; for; sake. of: clearness.

3:=Claims. (Cl. NSF-32.85)

2 The contact elements are retained in the apere. tures 2 and project beyond the lower surface 4 or base iso as to constitute tags 5 tovJh-ich'leads to said contact elements can-be soldered. The socket-illustrated is designed for use with pressedglassbase valves, the base ofthe" valvehaving a? central spigot which'may have a'longitudinal rib; and the socket is provided with acentr-al aperture s for receiving:thespigot and having a long 'i tudinat groove therein so. thatnif the valve spigot" isprovided with a rib, said rib wiii 00- operat'e with the-groove T to ensure proper orienta ien of the valve-inthe socket; The apertures '2 formed in said basefor the reception of the contactelements 'are i'n the example illustrated of" a substantially semicircular shapecross-section at their'upper ends 3'; with the arcuate walls 9 'innermost, 11 e;, towards the centre of said base, but the apertures may have another-j but preferablyan equivalent shape such as rhomboidal or trun cated' triangular shape. At their lower ends; lfl said apertures are ofrectangular form withtheminor axis radially arranged with respect to-the centre of said base, these rectangular ends receiving the ends of saidcontact elements which project through. said base. "Theouter-wall l I of each upper end 8- 01 said" apertures is preferably slightly convex assshown or it may be provided with a central long-itudinal rib. The arcu'ate Wall Qioff each ofsaid apertures is: provided with a longitudinal groove 12 of a "size" sufficient to re ceivethezcontact pinv on the valveand to afiord sufiicient tolerance to accommodate inaccuracies in manufacture of'the valve-. Theupper endsaot each groovel2, i; e. at the: surface of""said base where. the. contact: pins. are" inserted .are countersunk. as: shown at t3"; so: as to: guide the contact, pins: into the grooves; 12. Between each. of the: apertures: 2, on: the: upper surface of said base.v radially-disposed: ribs Mamay be provided solas;

to. increasezthe; leakage. path between the. contact: elements when: the; latter arcl'assembled' base.-

Thercontactelements -3."are-formed"fromstampw ings I5 (Figure 3' of thin brass: orother suit able material and the fiat blanks; from which the contact elements-are made. are generally on a somewhat rectangular form, one end or'eaclr' blank being formed with fiangestfi which are" folded over: at the dotted- 1 lines: I1 towards each; other so'as: to. form an end: portion ortag 5 which;

is relatively rigid and of a shape to pass through the rectangular ends lifl of the apertures -iriasaid base, but. to be aclose. fit; therein.v 'lhev flanges have projecting Wings 19 which, when the contact elements are inserted into the apertures 2 from the upper surface of the base i with the flanges folded over, are arranged to pass out of the lower ends of the apertures 2 and thereupon spring slightly apart (as indicated in Figure 2), engaging the lower surface 4 of the base I and thereby holding the contact elements in position. The end portion 5 of each of the contact elements 3 is provided with a longitudinal slot 18 through which a lead can be passed and soldered to said end after the contact elements are assembled in said base I. When the flanges l6 are folded over as above-mentioned, shoulders 2| are formed on each contact element, said shoulders being adapted to be seated on shoulders 22 formed in the apertures 2 in the base I where the apertures change from their semicircular cross-section to their rectangular crosssection. In addition the upper edges of the wings l9 which edges engage the lower surface 4 of the base I, are arcuate as shown in Figure 3, so that as the wings l9 spring apart they pull the shoulders 2| firmly against the shoulders 22,

and hold the contact elements 3 firmly in position, even though the depths of the ends ll) of the apertures 2 may not be equal in all cases. From the shoulders 2! each contact element tapers down to a rectangular portion 23 and between the tapered portion and the end of said rectangular portion a longitudinal slot 24 is provided. The end 25 of said rectangular portion is then bent over the longitudinally slotted portion 2] at the line 26, and then the portion 21 is bent over the tapered portion 28 at the line 29 so that the portion 23 then has the configuration shown in Figure 2. Alternatively a single loop may be formed by folding over the end of said rectangular portion. When the contact elements 3 are inserted in the apertures 2 the longitudinal slots 24 face the longitudinal grooves [2 provided in said apertures. The folded-over end portion 25 of the each contact element bears against the aforesaid tapered portion 28 and affords a degree of resiliency so that when the contact pin on the valve is inserted it is engaged by the slotted portion 21 and tends to be resiliently urged against the wall of the longitudinal groove I2. The tapered portion is preferably bent as shown in Figure 2, at an angle of about 30-. with the longitudinal axis of the contact element. In order to assemble the contact elements 3 in the base I it is merely necessary to pass the contact elements 3 through said apertures 2, the end portions which form the contact tags 5 passing through the rectangular portion H] of said apertures, until stopped by inter-engagement of said shoulders 2| and 22. The convex walls H of the apertures 2 or said longitudinal ribs thereon, provide fulcrums about which the contact elements 3 can rock, as can be seen in Figure 1, to accommodate contact pins which are angularly misplaced, said tapered portions 28 allowing such pivoting movement to occur. when a valve is inserted in the socket the valve pins are accommodated in said longitudinal grooves l2 and engage the edges of the longitudinal slots 24 in the contact elements, the portions 25, 21 and 28 which are folded over being such as to afford a required amount of pressure between the contact elements and the valve pins. Since the latter engage the edges of said longitudinal slots 24 a selfcleaning action occurs.

The central aperture 6 in said base I is preferahly provided with a contact-making element 30 which comprises a sleeve made of brass or other suitable material, the sleeve being formed from a fiat blank 3| (see Figure 4) bent to a substantially circular form and of such a size that when inserted in said central aperture it requires to be compressed so as resiliently to hold said sleeve in said aperture. If desired, protuberances 32 may be pressed in the wall of said sleeve, said protuberances being received in suitable slots or recesses 33 formed in the wall of the central aperture 3. The upper end of said sleeve is provided with a series of lugs 34, or may alternatively be provided with a flange, which limits the movement of said sleeve through said central aperture, whilst the other end of said sleeve may be provided with a soldering tag 35 and with one or more arms 36 which are bent so as to project towards, the centre of said central aperture and thereby ensure good contact between said sleeve and a valve provided with a metal spigot. In the example illustrated the sleeve is provided with a longitudinal groove 3'! corresponding to the groove i in the aperture 6 for receiving the longitudinal rib on the spigot of the valve.

The base I may be provided with suitable ears whereby it can be secured to the chassis of a radio receiver or, alternatively, said base may be secured in position on the chassis of a receiver by a separate attachment member 38 which is illustrated in position in Figures 1 and 2. In this latter case, said base may be provided around its periphery and intermediate the upper and lower surfaces thereof, with a circular flange 39 which is adapted to be seated on the chassis of the receiver indicated at 4B in Figure 2 and said attachment member 38, as illustrated, comprises a metal plate having a pair of cars 4| by means of which it can be screwed or otherwise secured to the chassis 459 and with an aperture 42 through which the upper surface of said base passes. With this construction the periphery of said base may be provided with a series of axial grooves 43 and said securing member 38 may be provided with a projection 44 so that, if desired, said base can be orientated in steps of for example 45 with respect to said attachment member, the base being prevented from rotation when said securing member is screwed down to the chassis by the projection 44 engaging one of said axial grooves 43.

What we claim is:

l. A socket for an electrical device comprising an insulating base having a passageway extending therethrough, said passageway adjacent one face of said base having a relatively large cross section, and adjacent the opposite face a relatively small cross-section, and an elongated removable contact member extending through said passageway, said member including an end portion folded upon itself along two lines normal to the longitudinal axis of said member with the end of said end portion lying between another portion of said member and the inner face of one of said folds, said folded end portion extending to said one face of said base and forming a resilient socket with a portion of a wall of said passageway for receiving a contact pin, whereby said end is displaced from contact with said pin to protect said end of said contact from excessive wear, the other end portion of said member having wings on opposite sides thereof foldable along lines parallel to the longitudinal axis of said member for stiffening said other end portion and for permitting entrance thereof through said passageway when said wings are folded to- 5 ward each other, and for fixing said member in said passageway when said wings are at least partly unfolded.

2. A socket for an electrical device comprising an insulating base having plurality of passageways therethrough, each of said passageways being formed by walls spaced differently from each other at two portions of said passageways adjacent opposite faces of said base, whereby said passageways are wider adjacent one face of said base than adjacent the opposite face thereof, and a contact member extending through each of said passageways, one end portion of said member being doubly folded upon itself along lines extending transversely of said member and being disposed in the wider portion of said passageways for forming a resilient socket for receiving a contact pin of said device, the other end portion of said member having lateral wings foldable toward each other to lie flat against said memher for insertion of said member through the {narrower portion of said passageways, said wings being urged to unfolded position for engaging an edge of said passageways for fixing {the position of said member in said passageways. '3. A socket for an electrical device comprising an insulating base, having a plurality of passageways therethrough, a portion of each of said passageways with the outer surface of the folded portion facing said concave wall end forming therewith a resilient receptacle for a contact pin "of said device, said member engaging said convex wall for rocking movement thereon on a longitudinal ,aiiis of said member her in said base.

CLIFFORD METCALFE.

RALPH SEXTON.

J R EFERENCES crrnnf lg references are of record in the file of this patent:

UNITED STATES PATENTS Number I Name Date Re. 20,162 Draving Nov. 10, 1936 1,741,221 Bremer Dec. 31, 1929 1,747,896 Gates :Feb. 18, 1930 1,811,464 Geloso ,June 23, 1931 1,936,320 Alden "in-Nov. 21, 1933 2,087,784 7 'f 193': 2,235,207 Eby Mar. 18, 1941 2,252,918 Del Camp Aug. 19, 1941 2,291,808 Henning -1. Aug. 4. 1942 2,369,541 Del Camp .J Feb. 13, 1945 j FOREIGN PA ENTS Number Country Date 44,128 Holland "L, May 5, 1931 263,415 England ;*Dec. 30, 1926 547,968 England Sept. 18, 1942 to 4475.31 Australia Oct. 12, 1931 

